This invention is directed to the providing of an oil water separator inlet delivery system, the utilization of which efficaciously enhances the performance of the oil water separator system in which it is used. Relatively recently, the importance of water quality and the impact of runoff on natural streams and watercourses has been recognized. Regulations, especially at the federal level, have been enacted to address this concern. Subsequent to federal action, states and local communities have enacted similarly focused legislation.
One particular area of concern is runoff from new construction, particularly parking lots. Another area of concern is workplaces where oil and grease accumulate on the floor until such a time as the washing of the floor causes them to enter the wastewater system. Regardless of the source of the runoff, there is considerable interest in trying to decrease the amount of sediment, oil, grease, and other contaminants ultimately being discharged into streams, rivers, and other bodies of water. Consequently, oil water separators have been developed for installation as part of a drainage system.
For example, an industrial user who controls or collects storm water and discharges it through a pipe, drain or other outlet, into a sewer system or navigable waterway must comply with the National Pollutant Discharge Elimination System (NPDES). Mandated by Congress under Section 402 of the Clean Water Act, the NPDES storm water program is a two-phased approach to eliminating or reducing accidental and chronic low-level releases of oil-polluted water. A working oil water separator can be an important part of a storm water drainage system designed for facility compliance with the NPDES storm water program.
There have been several attempts at providing oil water separator systems. Such processes and devices are typically used in parking garages, process plants, maintenance facilities and service stations that process storm water runoff or process water.
For example, Pank, U.S. Pat. No. 5,746,911, discloses an apparatus for separating a light from a heavy fluid, such as occurs as between oil and water from parking lot run-off. The system utilizes two large tanks connected to each other by a pair of conduits. Under most conditions, water flow enters the inlet tank flows into the separation tank, and then finally flows from the separation tank to the outlet conduit. However, when the system is subjected to a heavy rain, the fluid level in the inlet tank rises to a level at which there is a direct overflow into the outlet conduit.
Meanwhile, Keep, U.S. Pat. No. 5,229,015, discloses a liquid separator designed to separate a mixture of immiscible liquids of different densities, such as oil and water, wherein one of the liquids is in a discontinuous phase. A coalescing medium within the container encourages coalescence and agglomeration of the discontinuous phase liquid.
Norman, U.S. Pat. No. 4,844,819, discloses an oil and water separator having plural nested separating tanks. In one embodiment of the invention, plastic corrugated tubing is located in the separating tanks. A method for separating oil from water using the device is also disclosed.
Rice, U.S. Pat. No. 5,520,825, discloses an oil and water separator. A series of tubes in the dividing wall assist the liquid's oil particles pass out of the sludge chamber.
Sager, U.S. Pat. No. 5,505,860, discloses a grease and oil trap for separating and retaining grease, oil, and particulates from water or other fluids. The inlet fitting comprises a uniquely shaped deflecting cup.
Aymong, U.S. Pat. No. 4,722,800, discloses an oil and water separator. A velocity head diffusion baffle is positioned beneath the inlet orifice. Corrugated coalescer plates are positioned atop a sludge baffle.
Williamson, U.S. Pat. No. 6,290,545, discloses a drainwater treatment system. An elbow-shaped conduit provides passage through the barrier between the first and second compartments of the system.
To meet water runoff compliance regulations the stormwater drainage systems must be capable of removing the petroleum hydrocarbons from the natural water runoff at least down to 15 parts per million rpm), which includes the removal of all free oil droplets equal to or greater than 20 microns in size. As a result of regulations, it is apparent the need exists for an oil water separator which can effectively collect sediment as well as assist oil in separating from water.